Modernizing IT Infrastructure at Microsoft: A cloud-native journey with Azure

At Microsoft, we are proudly a cloud-first organization: Today, 98% of our IT infrastructure—which serves more than 200,000 employees and incorporates over 750,000 managed devices—runs on the Microsoft Azure cloud.

The company’s massive transition from traditional datacenters to a cloud-native infrastructure on Azure has fundamentally reshaped our IT operations. By adopting a cloud-first, DevOps-driven model, we’ve realized significant gains in agility, scalability, reliability, operational efficiency, and cost savings.

“We’ve created a customer-focused, self-serve management environment centered around Azure DevOps and modern engineering principles,” says Pete Apple, a technical program manager and cloud architect in Microsoft Digital, the company’s IT organization. “It has really transformed how we do IT at Microsoft.”

“Our service teams don’t have to worry about the operating system. They just go to a website, fill in their info, add their data, and away they go. That’s a big advantage in terms of flexibility.”

Pete Apple, technical program manager and cloud architect, Microsoft Digital

What it means to move from the datacenter to the cloud

Historically, our IT environment was anchored in centralized, on-premises datacenters. The initial phase of our cloud transition involved a lift-and-shift approach, migrating workloads to Azure’s infrastructure as a service (IaaS) offerings. Over time, the company evolved toward more of a decentralized, platform as a service (PaaS) DevOps model.

“In the last six or seven years we’ve seen a lot more focus on PaaS and serverless offerings,” says Faisal Nasir, a principal architect in Microsoft Digital. “The evolution is also marked by extensibility—the ability to create enterprise-grade applications in the cloud—and how we can design well-architected end-to-end services.”

Because we’ve moved nearly all our systems to the cloud, we have a very high level of visibility into our network operations, according to Nasir. We can now leverage Azure’s native observability platforms, extending them to enable end-to-end monitoring, debugging, and data collection on service usage and performance. This capability supports high-quality operations and continuous improvement of cloud services.

“Observability means having complete oversight in terms of monitoring, assessments, compliance, and actionability,” Nasir says. “It’s about being able to see across all aspects of our systems and our environments, and even from a customer lens.”

Decentralizing our IT services with Azure

As Microsoft was becoming a cloud-first organization, the nature of the cloud and how we use it changed. As Microsoft Azure matured and more of our infrastructure and services moved to the cloud, we began to move away from IT-owned applications and services.

The strengths of the Azure self-service and management features means that individual business groups can handle many of the duties that Microsoft Digital formerly offered as an IT service provider—which enables each group to build agile solutions to match their specific needs.

“Our goal with our modern cloud infrastructure continues to be a solution that transforms IT tasks into self-service, native cloud solutions for monitoring, management, backup, and security across our entire environment,” Apple says. “This way, our business groups and service lines have reliable, standardized management tools, and we can still maintain control over and visibility into security and compliance for our entire organization.”

The benefits to our businesses of this decentralized model of IT services include:

• Empowered, flexible DevOps teams
• A native cloud experience: subscription owners can use features as soon as they’re available
• Freedom to choose from marketplace solutions
• Minimal subscription limit issues
• Greater control over groups and permissions
• Better insights into Microsoft Azure provisioning and subscriptions
• Business group ownership of billing and capacity management

“With the PaaS model, and SaaS (software as a service), it’s more DIY,” Apple says. “Our service teams don’t have to worry about the operating system. They just go to a website, fill in their info, add their data, and away they go. That’s a big advantage in terms of flexibility.”

“The idea of centralized monitoring is gone. The new approach is that service teams monitor their own applications, and they know best how to do that.”

Cory Delamarter, principal software engineering manager, Microsoft Digital

Leveraging the power of Azure Monitor

Microsoft Azure Monitor is a comprehensive monitoring solution for collecting, analyzing, and responding to monitoring data from cloud and on-premises environments. Across Microsoft, we use Azure Monitor to ensure the highest level of reliability for our services and applications.

Specifically, we rely on Azure Monitor to:

Because we’ve moved to a decentralized IT model, much of the monitoring work has moved to the service team level as well.

“The idea of centralized monitoring is gone,” says Cory Delamarter, a principal software engineering manager in Microsoft Digital. “The new approach is that service teams monitor their own applications, and they know best how to do that.”

Patching and updating, simplified

Moving our operations to the cloud also means a simpler and more automated approach to patching and updating. The shift to PaaS and serverless networking has allowed us to manage infrastructure patching centrally, which is much more scalable and efficient. The extensibility of our cloud platforms reduces integration complexity and accelerates deployment.

“It depends on the model you’re using,” Nasir says. “With the PaaS and serverless networks, the service teams don’t need to worry about patching. With hybrid infrastructure systems, being in the cloud helps with automation of patching and updating. There’s a lot of reusable automation layers that help us build end-to-end patching processes in a faster and more reliable manner.”

Apple stresses the flexibility that this offers across a large organization when it comes to allowing teams to choose how they do their patching and updating.

“In the datacenter days, we ran our own centralized patching service, and we picked the patching windows for the entire company,” Apple says. “By moving to more automated self-service, we provide the tools and the teams can pick their own patching windows. That also allowed us to have better conversations, asking the teams if they want to keep doing the patching or if they want to move up the stack and hand it off to us. So, we continue to empower the service teams to do more and give them that flexibility.”

Securing our infrastructure in a cloud-first environment

As security has become an absolute priority for Microsoft, it’s also been a foundational element of our cloud strategy.

Being a cloud-first company has made it easier to be a security-first organization as well.

“The cloud enables us to embed security by design into everything we build,” Nasir says. “At enterprise scale, adopting Zero Trust and strong governance becomes seamless, with controls engineered in from the start, not retrofitted later. That same foundation also prepares us for an AI-first future, where resilience, compliance, and automation are built into every system.”

Cloud-native security features combined with integrated observability allow for better compliance and risk management. Delamarter agrees that the cloud has had huge benefits when it comes to enhancing network security.

“Our code lives in repositories now, and so there’s a tremendous amount of security governance that we’ve shifted upstream, which is huge,” Delamarter says. “There are studies that show that the earlier you can find defects and address them, the less expensive they are to deal with. We’re able to catch security issues much earlier than before.”

“There are less and less manual actions required, and we’re automating a lot of business processes. It basically gives us a huge scale of automation on top of the cloud.”

Faisal Nasir, principal architect, Microsoft Digital

We use Azure Policy, which helps enforce organizational standards and assess compliance at scale using dashboards and other monitoring tools.

“Azure Policy was a key part of our security approach, because it essentially offers guardrails—a set of rules that says, ‘Here’s the defaults you must use,’” Apple says. “You have to use a strong password, for example, and it has to be tied to an Azure Active Directory ID. We can dictate really strong standards for everything and mandate that all our service teams follow these rules.”

AI-driven operations in the cloud

Just like its impact on the rest of the technology world, AI is in the process of transforming infrastructure management at Microsoft. Tasks that used to be manual and laborious are being automated in many areas of the company, including network operations.

“AI is creating a new interface of agents that allow users to interact with large ecosystems of applications, and there’s much easier and more scalable integration,” says Nasir. “There are less and less manual actions required, and we’re automating a lot of business processes. Microsoft 365 Copilot, Security Copilot, and other AI tools are giving us shared compute and extensibility to produce different agents. It basically gives us a huge scale of automation on top of the cloud.”

Apple notes that powerful AI tools can be combined with the incredible amount of data that the Microsoft IT infrastructure generates to gain insights that simply weren’t possible before.

“We can integrate AI with our infrastructure data lakes and use tools like Network Copilot to query the data using natural language,” Apple says. “I can ask questions like, ‘How many of our virtual machines need to be patched?’ and get an answer. It’s early, and we’re still experimenting, but the potential to interact with this data in a more automated fashion is exciting.”

Ultimately, Microsoft has become a cloud-first company, and that has allowed us to work toward an AI-first mentality in everything we do.

“Having a complete observability strategy across our infrastructure modernization helps us to make sure that whatever changes we’re making, we have a design-first approach and a cloud-first mindset,” Nasir says. “And now that focus is shifting towards an AI-first mindset as well.”